Low-water alarm.



H. NEVLLE.

LOW WATER ALARM.

APPLIUATION FILED APRA ma,

LEQQ; @Agn Patented June 9, w14.

@gana A ffm/@mmm H. NEVILLE.

LOW WATER ALARM.

APPLICATION FILED AMM, 191s.

Mmmm@ @muted Jun@ 9,1m.

2 SHEETSASHEBT 2.

UNiTED STATES 'PATENT OFFICE.

HARRY NEVILLE, 0F LOS ANGELES, CALIFORNIA, ASSIGNOR OFIONE-FIFTH TO PATRICK SHEEDY, ONE-FIFTH T0 GEORGE H. GOODWIN, ONE-FIFTH T0 DANIEL KELLOGG, AND ONE-FIFTH T0 WILLIAM F. MERRY, ALL 0F LOS ANGELES,-.GALI

` FORNIA.

Vitow-wafi-iin ALARM.

Specification of Letters Patent.

Patented lune 9, 1914.

To all wliom it may concern Be it known that I, HARRY NEVILLE, a citizen of the United States, residing at Los i'lngeles, in the county of Los Angeles and State of California, have invented certain new and useful Improvements in Low-Water Alarms, of which the following is a specification.

This invention relates to improvements in safety devices for steam boilers, and especially for the steam boilers of locomotives,

and by the use of which devices the explosion of such boilers is prevented.

The immediate object of the invention is to improve the construction of the low water alarm apparatus shown and described 1n Letters Patent of the United States No. 1,004,896 issued to me October 3, 1911, and No. 1,015,703 issued to me January 23, 1912,

whereby the apparatus is rendered more etlicicnt and reliable.

With these and other objects in view, .the invention consists of certain novel features of construction, combination and ada tation of the parts as will be more fully hereinafter pointed out.

ln the accompanying drawings, Figure 1 is a central vertical section of the apparatus; Fig. 2 is a vertical section of a portion of the apparatus on the plane of the line 2 2 in Fig. 1, and a side elevation of the parts back of the section plane; Fig. 3 is a central vertical section of a modified form of the valve; and Fig. 4 is vertical section of a part of such modified form on the plane of the line 4--4 in Fig. 3, and a side elevation of the parts back of the section plane; and Fig. 5 is a front view of a locomotive boiler showing the application ofthe invention thereto.

Referring to the drawings, 1 denotes the steam boiler of a locomotive on which there is arranged at any suitable point the iinproved automatic apparatus, the saine being shown as arranged on the front of the boiler and connected thereto at a point which vhas. been determined upon as a low water level.

3 is a steam and water shell or cylinder having on one side an apertured lug 4 whereby it mayv be bolted or otherwise secured to the boiler. On the side of the shell 3 opsite the lug `4 there is formed a' wing 5 ving formed therein a vertically disposed and suspended within the shell 3, as herein- I after described, is a cup 16 adapted to contain a mass of mercury indicated at 160, an annular s ace 9 being left between the outer surface o the cup and the inner surface of the cylinder 3, and a space 90 being left below the cup and above the bottom of the cylinder, and which space connects with the passage 8 by a passage 91.

The lower end of the passage 91 is closed by a plug 12 which, when removed, permits any sediment to be washed out of the cylinder and the latter is thus kept clean. It will be noted, however, that the lowest portion of the passage S'terminates internally at the lowest portion of the shell 3 without any chamber or pocket below the levelfof the passage 8, so that when circulation takes place through the passages 8, 6 and 7, any foreign matter which might have a tendency to accumulate in the passage 8 is not permitted to do so but will be washed back into the boiler. As a result and effect of the circulation of the steam and water in these passages, the shell 3 will be kept clean from deposits. This arrangement forms a selfcleaning feature for this shell. which is important for a proper and reliable operation of the device.

The passage 6 serves as a receiving chamber for such steam as may escape from the boiler when, by reason of the swaying of the locomotive, the water momentarily uncovers the connection 10. Such steam will pass into the annular space 9 surrounding the mercury cup'16, but, owing to the presence of the air space 11 between the passage 6 and the cylinder 3, the temperature of the steam vwill be reduced suiciently to prevent the expansion of the mercury until the water has uncovered the pipe 8 for a sutliciently larged open upper end 15 of the mercury cup 16. On this end 15 there is formed an annular flange 17 which, when the cup 16 is screwed down into the cylinder 3, comes into engagement with the lupper surface of the latter and thus forms a tight joint between the cup and the cylinder, as indicated at 300. The cup 16 is itself internally threaded near its .upper end as at 18 and above such threaded portion is expanded to form a shoulder 19, above which it is still further enlarged and threaded as at 20.

Screwed into engagement with this threaded part 2O is the reduced threaded lower end of a steam valve casing 21, at the upper end of which is arranged a valve seat 22 adapted to be engaged by a valve 23. The casing 21 is provided with an annular flange 240 surrounding and leading to a steam inlet passage 24, and with a simllar annular iiange 250 surrounding and leading to a steamdischarge passage 25. To vthe liange 240 is connected a steam conductmg pipe 26 leading from and connectlng with a turret or steam dome 27, or some other part of the device from'which steam may be taken from the boiler. To the flange 250 there'is lconnected a conduit 280 leading to a control valve 28,to the discharge end of which is connected a steam conducting pipe 29 leading to an alarm whistle 31 arranged at any suitable point, and which pipe 29 1s provided with a branch 30 which leads to and is oonnected with a suitable operating mechanism 32 .for controlling the fuel supply valve of thel burner if liquid fuel is used, or to a .water spray valve 320 for spraying the re with water from the boiler in case solid fuel is used. The re'control mechanisms 32 and 320 formA no part of the present invention and are therefore not illustrated in the drawings. The body 'of the control valve 28 is provided between its inlet and discharge ends with a partition 281 provided with a seat 282 adapted to be engaged by a globular seat 283 of a valve stem 284, which stem is actuated partly by thepartition 281 and partly by a cap 285 let into the upper portion of the valve body and held in position by a retaining nut 286. The lower inner edge 287 of the cap ring 285 constitutes a seat adapted to coperate with the upper part of the globular seat 283 on the stem 284.

The valve stem 284 terminates in an upper head 288 between which and the nut 286 there is placed a spring 289 which holds the stem 284 with its connected parts normally in an open position. Passing through the cap 285 is a small passage 290 adapted to permit thev escape of the steam to the outer a1r` v The valve 23 is provided'withy a stem 33 which projects downwardly in the casing 21 through a stuing box indicated at 34, and which includes a packing nut v35, the head of which projects into an open cage 36 formed on the lower portion of the valve casing 21. In this head there is formed an annular series of vertical notches 37 which may be engaged through the open cage 36 by a spanner wrench to adjust the nut. In the lower end of the valve stem 33 there is a threaded socket; 38 into which is fitted an adjust-ing screw`39, by means of which the length ofthe valve stem is increasedor diminished, and consequently the length of its stroke is increased or diminished. The lower end of thisscrew 39 terminates in a square head 40 to receive a wrench by means of which it may be moved.

On top of the valve casing 21 there is placed a closing cap 400 inside of which is a spring 401, the purpose of which is to assist in returning the valve 23 to its seat after it has been raised. Arranged in the cage 36 and having a threaded engagement at its lower end with the upper portion 18 Y of the mercury cup 16, is a tube 41 provided with an annular flange 42 which, when' the tube 41 is rcrewed down into the upper end of the cup 16, engages the shoulder 19.

Slidably mounted inthe tube 41 is a plunger seat andv steam will be permitted to pass through' the valve from the pipe 26 to the pipe 29. (and 30) to sound the'alarm (and actuate thefuel extinguishing mechanism).

The upper end of the plunger 43. is provided witha slot 45 through which there is adapted to pass a lever 451 pivoted at 452 and normally resting on a stop 453 secured to any convenient point on the valve casing 21. The lever 451 provides means for manually moving the plunger and returning it to its normal position after it has been raised by the expansion of the merc'ury, and it also provides means for testing the operative condition of the alarm by manually lifting the plunger 43 into contact with the lower end of 'the valve stem 3 3. The lower end of the plunger'43 is recessed as at- 431 providing,

The Smm-1g b'ox 44 "is provided with an v adjustinge cap nut 46 in which is formed an annular series of vertically disposed notches 47 which through the open cage 36 may be engaged by a s anner wrench to elect the adjustment o this nut. With the notches 37 of the packing adjusting nut 35 of the stuiling box 34, and the notches 47 of the adjusting cap 46, are engaged s ring actuated locking dogs 48 which are sli ably mounted in hollow plugs 49 arranged in one side of the cage 36. 'llhe dogs 48 are provided with reduced stems 50 around which are coiled springs 51 arranged in the outer ends of the plu s 49, whereby the dogs are forced inwar y into engagement with the notches 37 and 47 to lock their respective nuts against casual loosening.

ln the upper end of the cup 16 there is formed a drain passa e 52 which communicates with the s ace etween the upper end of the cup anl the valve casing 21, thus permitting any water which accumulates 1n this, space to escape therefrom. lt will be noted that the apparatus is located entirely outside of the boiler and exposed to the atmosphere, which arrangement is an important feature in connection with the operation of the device.

In the modification shown in Figs. 3 and 4, the spring 401 isdispensed with and the return of the valve 23 and the plunger 43 to their normal positions after the alarnrhas been sounded, is effected in an entirely manual way by means of the lever 451. For this purpose, the adjusting screw 39 is provided with a hollow cylindrical ex tension 53 into which enters a cylindrical extension of the plunger 43 which is provided With a longitudinal slot. A pin 54 passes through the extensions of both the adjusting screw and the plunger. While the pin is passed in the wall of .the extension 53, it permits of the free movement of the plunger in the extension within the limits of the slot in the plunger extension. 4 The operation of the device is as follows: The cup 1G is filled with mercury and the device connected to the boiler as shown in Fig. 5, with the connection 10 arranged at a point which is considered to be the low water level and below which 'ordinarily the level of the water in the boiler should not be permitted tofall. As long as the connection 10 is under water, the water from the boiler will pass through the passage 8 into the shell 3 filling the latter, and also the passages 6 and 7. The water thus let into the'y shell 3 will be cooled by the exposed position of the latter to the atmosphere, and its heat will be insuflicient to cause the mercury in the cup 16 to expand. When, however, the water in the boiler sinks below the level of the water in the passage 8, the shell 3 will be drained of water and steam from the boiler will enter it. When steam has entered' the shell, its heat willv cause the mercury in the cup 16 to expand and to rise into engagement with the plunger 43 as its movement is restricted in every other direction, thereby forcing the plunger upward into enga ment with the valve stern 33 (or the a justing screw 39 when one is provided), and conseguenti lifting the valve 23 oli from its seat 22, w iereupon steam from the boiler will pass from the pipe 26 through this valve and through the connection 280 and' through the control valve 28 to thevpipe 29 so that the alarm whistle will sound a warnin and if the branch 30 is provided with t e apparatus, the steam will pass to the combustion controlling device to shut oil the fuel supply when oil is used, or to spray the fire when coal is used. After the whistle alarm has sounded, the operator should put the water feeding apparatus oi.= the boiler into action to fill the boiler with water up to its normal level. When this is done and the water again fills the shell 3, it will tend to cool the mercury 160 but it will take some time before this mercury is cooled sutliciently to permit the plunger 43 and valve 23 to return to their normal positions, either by pulling down the lever 451 or automatically through the actionv of the sl ring 401, and in the meantime the steam rom the boiler will be passing through both of the valves andv the whistle will continue to sound. f

This is undesirable, and in order to stop it the valve stern of the control valve 28 is pushed down by pressing on the cap 288. This will stop the further passage of the steam to the whistle (and also to the fuel extinguishing devices), and the valve 283 will b e held to its seat by the steam acting on its upper side. At the same time a slight flow of steam will take place and leak through the small passage 290 indicating to the operator that the valve 28. has been closed and that the apparatus is not in Aan operating condition. As soon as the valve 23 is'returned to its seat, the valve 28 will open automatically under the influence of its spring and then the apparatus will again be in an operating condition should the water level again drop below the level of the connection 10.

It will be seen from the above description that the lever 451 has the double function of returning the plunger 43 and valve 23 to their normal positions after the alarm has sounded, and of enabling the operator to test the operative condition of the apparatus by manually actuating the valve 23 to vsee that all of the steam assages from the boiler to the whistle are c ear. The control valve 28 steani from the'passage 290 that the valve 23 and plunger 43 are now in their normal positions. v

What I claim is: 1. In low water alarm of the character described, the combination with an alarm and a pipe leading thereto, of mechanism controlled bythe low water for admitting fluid under pressure to the pipe to operate the alarm, a separate normally open valve in said pipe, means for manually movingv the valve to closed position, and means actuated by the fluid under pressure in the pipe for holding it closed after said manual movement.

2. In low water alarm of the character described, the combination with an alarm and apipe leading thereto, of mechanism controlled by the low water for admitting iuid under pressure to the pipe tooperate the alarm, a separate normally open valve in said pipe, means for' manually moving the valve to closed position, means actuated by the fluid under pressure inthe pipe for holding it closed after said manual movement, and means for automatically reopening the valve when theiiuid pressure has been cut oil the said pipe.

3.' A low water alarm for locomotive boilers and the like comprising an alarm, a steam conduit leading from the steamf-space of the boilerl to the alarm, a valve normally closed arranged on said conduit and adapted to be opened automatically when the water inthe boiler sinks below a predetermined level and to allow the steam to pass to the alarm, and means for preventing the prolonged sounding 'of the alarm including a second valve normally open in the steam line leading to the alarm and means for manually closing it.

4. A low water alarm for locomotive boilers and the like comprising an alarm, a steam conduit leading from the steam space of the boiler to the alarm, a valve normally closed arranged on said conduit and adapted to be opened automatically when the water in the boiler sinks below a predetermined level and to allow the steam to pass to the alarm, and means for preventing the prolonged sounding of the alarm, in combination with means for indicating whether the described device is in operative condition including a second valve in the steam line leading to the alarm and which valve when closed is provided with a steam leak.

5. A low water alarm for locomotive boilers and the like comprising an alarm, a steam conduit leading from the steam space of the boiler to the alarm, a valve normally closed arranged on said conduit and adapted to be opened when the water in the boiler sinks below a predetermined level to allow the steam to pass from the boiler to the alarm, and a second valve on the steam line leading to the alarm and provided with means wherebyl1 `it is held normally open, and 4means w ereby it may be manually closed.

6. A low water alarm for locomotive boilers and the like com risin an alarm, a steam conduit leadin iromte steam space of the boiler to the a arm, a valve normally closed arranged on said conduit and adapted to be opened when the water in the boiler the steamto pass from the boiler to the alarm, and a second'v'alve on the steam line vleading to the alarm and provided with means for automatically opening the same whereby it is held normally open, and means whereby it may be closed and kept closed so long as steam is passing alongthe steam line to the alarm.

7 A low water alarm for locomotive boilers and the like comprising an alarm, a steam conduit leading from the steam space of the boiler to the alarm, a valve normally to be opened when the water in the'boiler ,sinks below a predetermined level to allow alarm, and a second valve on the steam line leading to* the alarm ,and provided with means .whereby itis held normallyopen, and means whereby it may be closed and the steam line to the alarm, and further means whereby when so closed its condition is visually indicated.

8. A low water alarm for locomotive boilers and the like comprising an alarm, a steampconduit leading from the steam space .of the.v boiler to the alarm, a valve normally closed arranged on said conduit and adapted to be opened when the water in the boiler the steam to pass from the boiler' to the alarm, and a second valve on the steam line leading to the alarm and provided with means whereby it is held normally open, and means whereby it may be closed and kept closed so long as steam is passing along the steam line to the alarm, and further means whereby when so closed its condition is visually indicated including a steam leak.

9. A low water alarm for locomotive boilers and the like comprising anl alarm, a steam conduit leading from the steam space of the boiler to the alarm, a valve normally closed arranged on said conduit and adapted to be opened when the water in the boiler sinks below a predetermined level toA allow the steam to pass from the boiler to the alarm, and a second valve on the steam line leading to the alarm and provided with means whereby it is held normally open, means whereby it may be closed and kept closed so long as steam is passing along the sinks belowy a predetermined. level to allow 'the steam to'pass from the boiler to thesinks below a predetermined level to allow steam line to the alarm, and further means.

losedarranged on saidconduit and adaptkept closed so. long as steam is passing along lll llli

whereby it Iis automatically opened as soon as steam ceases to pass along the line to the alarm. l

10. A low water alarm for llocomotive boilers and the like comprising an alarm, a steam conduit leading from the steam space of the boiler to the alarm, a valve normally closed arranged on said conduit and adapted to beopened when the water in the boiler sinks below a predetermined level to allow the steam to pass from the boiler to the alarm, and a second valve on the steam line leading to the alarm and provided with means whereby it is held normally open, means whereby it may be closed and kept closed so long as steam is passing along the steam line to the alarm, and further means whereby it is automatically opened as soon as steam ceases to pass along the line to the alarm, including a spring normally under compression.

ll. A low water alarm for locomotive boilers and the like comprisin an alarm, a steam conduit leading from t e steam space of the boiler to the alarm, a valve normally closed arranged on said conduit and adapted to be opened when the water in the boiler sinks below a predetermined level to allow the steam to pass from the boiler to 'the alarm, and a second valve on the steam line leading to the alarm and provided with means whereby it is held normally open, means whereby it may be closed and kept closed so long as steam is passing along the steam line to the alarm, further means whereby when so closed its condition is visually indicated, and further means whereby it is automatically opened as soon as steam ceases to pass along the line to the alarm.

12. In low water alarm of the character described, the combination with an alarm and a pipe leading thereto, of mechanism controlled by the low water for admitting iiuid under pressure to the pipe to operate the alarm, a separate normally open valve in said pipe, means for moving the valve to closed position, and means held inactive by the Valve when the same is open and thrown into action when the valve is closed to indicate the closed position of the valve.

13. ln low water alarm of the character described, the combination with an alarm and a pipe leading thereto, of mechanism controlled by 'the low water for admitting fluid under pressure to the pipe to operate the alarm, a separate normally open Valve y in said pipe, means for moving the valve to closed position, and a Vent passage held 'closed by the Valve when the same is open and opened when the valve is closed to indcate the closed position oilE said valve.

14C, ln low water alarm of the character described, the combination with an alarm and a pipe leading thereto, of mechanism controlled by the low water for admitting fluid under pressure to the pipe to operate the alarm, a separate normally open valve in said pipe, an exposed handle' for manually closing the valve, said Valve having` a surface acted against by the Huid under pressure in the pipe to hold the valve closed after its manual actuation, and a spring operating against the Valve to reopen it when the pressure against the surface is removed.

lln testimony whereof l aliix my signature in presence of two witnesses.

HARRY NEVILLE. Witnesses:

CLARENCE Gr. CAMPBELL, EDNA A. MORELAND. 

